This story revolves around Rivera Ryu. A reincarnated person. Before reincarnation, his soul was actually in two parts in two different bodies. One in Mizutani Ryu a Highschool boy and Demon lord Mictian . Only memories of one part get transferred but personality is a mix of both. The Goddess who reincarnated him didn't give him a Goal saying he'll know if it's him. Getting into a troublesome situation as soon as reincarnated. The protagonist takes a vow "If it is a new world, I will set my own Goals".